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signed to it by Dr. Buckland and Mr. Conybeare on the shore of 

 Cushendan Bay, belongs to a conglomerate associated with the new 

 red sandstone. It is described as consisting principally of a coarsely 

 grained, whitish sandstone, containing in its upper part fragments of 

 quartz and porphyry, but no pebbles of granite or mica-slate. It is 

 stated to alternate both with the subjacent mica-slate and the super- 

 incumbent new red conglomerate, and it is said to contain also beds of 

 porphyry. The strata dip conformably to those of the mica-slate, but 

 the angle of inclination gradually decreases from 65° to 30° as the 

 formation recedes from the latter rock. 



Porphyry. — Several varieties of this rock are stated to occur, the 

 most common having a claystone base. The author conceives, as it 

 frequently alternates with the old red sandstone, but never with the 

 new red conglomerate, that it constitutes the essential character by 

 which these deposits may be distinguished from each other. 



The carboniferous limestone — is merely alluded to as occurring on 

 the sea shore near Fairhead. 



The coal measures — are stated to consist of the usual alternations 

 of coal, shale, sandstone, and ironstone ; to rest at their northern 

 boundary on the mountain limestone and old red sandstone ; and at 

 their southern on mica-slate ; and to be overlaid by the great basaltic 

 deposit of Fairhead. 



New red sandstone and conglomerate. — The conglomerate occur- 

 ring on the shore of Cushendan Bay, the author separates from the 

 old red sandstone to which it had been previously assigned, and con- 

 siders it as a member of the new red sandstone. His reasons for 

 making this separation are, that it is identical in character with the 

 conglomerate which overlies the coal measure in Murloch Bay ; that 

 it contains pebbles of granite and mica-slate, which are never found 

 in the old red sandstone ; that the latter formation alternates with 

 mica-slate, but that the conglomerate when in contact with that rock, 

 does not alternate with it, but reposes unconformably upon it; and 

 that the old red sandstone contains beds of porphyry which are never 

 found in the conglomerate. The author, however, states that the 

 conglomerate alternates with the old red sandstone as well as with 

 the new red sandstone ; and he admits that the whole series of 

 strata between the mica-slate and the chalk must be regarded as 

 one great mechanical deposit, produced by the operation of the same 

 cause, occasionally modified in intensity. 



The upper division of this formation consists of the usual varieties 

 of red sandstone and red marl with gypsum. 



Lias, the next stratum described, consists entirely of shale, and 

 occurs only on the southern shore of Cushendan Bay. 



The mulatto is divided by the author, in conformity with the cha- 

 racters assigned to it by Dr. Berger, into two parts? — the upper con- 

 sisting of a homogeneous sandstone, and the lower of a conglomerate 

 containing quartz pebbles, and fragments of mica-slate and white 

 limestone. These two varieties are said to be constant in their cha- 

 racters and position, and to form a band varying from 9 inches to 10 

 feet in thickness from Gerron Point to Teabuliadh mountain. 



